Adjunctive chemotherapy with bisphosphonates has been reported to delay bone metastasis and improve overall survival in breast cancer. Aside from its antiresorptive effect, bisphosphonates exhibit antitumor activities, in vitro and in vivo, via several mechanisms, including antiangiogenesis. In this study, we investigated the potential molecular mechanisms underlying the antiangiogenic effect of non-nitrogen-containing and nitrogen-containing bisphosphonates, clodronate and pamidronate, respectively, in insulin-like growth factor (IGF)-1 responsive human breast cancer cells. We tested whether bisphosphonates had any effects on hypoxia-inducible factor (HIF)-1a/vascular endothelial growth factor (VEGF) axis that plays a pivotal role in tumor angiogenesis, and our results showed that both pamidronate and clodronate significantly suppressed IGF-1-induced HIF-1a protein accumulation and VEGF expression in MCF-7 cells. Mechanistically, we found that either pamidronate or clodronate did not affect mRNA expression of HIF-1a, but they apparently promoted the degradation of IGF-1-induced HIF-1a protein. Meanwhile, we found that the presence of pamidronate and clodronate led to a dose-dependent decease in the newly-synthesized HIF-1a protein induced by IGF-1 in breast cancer cells after proteasomal inhibition, thus, indirectly reflecting the inhibition of protein synthesis. In addition, our results indicated that the inhibitory effects of bisphosphonates on the HIF-1a/VEGF axis are associated with the inhibition of the phosphoinositide 3-kinase/AKT/ mammalian target of rapamycin signaling pathways. Consistently, we demonstrated that pamidronate and clodronate functionally abrogated both in vitro and in vivo tumor angiogenesis induced by IGF-1-stimulated MCF-7 cells. These findings have highlighted an important mechanism of the pharmacological action of bisphosphonates in the inhibition of tumor angiogenesis in breast cancer cells.Breast cancer is the leading cancer affecting millions of women worldwide with aggressive osteolytic bone metastases in the advanced diseases 1,2 and longstanding morbidity or skeletal complications, including bone pain, pathological fracture, hypercalcemia, spinal cord or nerve root compression syndrome. 3 Bisphosphonates are synthetic analogs of inorganic pyrophosphate, containing a phosphorus-carbon-phosphorus (P-C-P) backbone and variable side chains that determine the specific potency for inhibition of bone resorption. 4,5 Bisphosphonates that lack a nitrogen functional group in the R2 side chain (such as clodronate) condense with an

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Five Chinese herbal medicines--matrine, oxymatrine, sophoridine, artemisinin, and dihydroartemisinin--were investigated using vibrational circular dichroism (VCD) experiments and density functional theory calculations to extract their stereochemical information. The three matrine-type alkaloids are available from the dry roots of Sophora flavescens and have long been used in various traditional Chinese herbal medicines to combat diseases such as cancer and cardiac arrhythmia. Artemisinin and the related dihydroartemisinin, discovered in 1979 by Professor Youyou Tu, a 2015 Nobel laureate in medicine, are effective drugs for the treatment of malaria. The VCD measurements were carried out in CDCl3 and DMSO-d6, two solvents with different dielectric constants and hydrogen-bonding characteristics. A "clusters-in-a-liquid" approach was used to model both explicit and implicit solvent effects. The studies show that effectively accounting for solvent effects is critical to using IR and VCD spectroscopy to provide unique spectroscopic features to differentiate the potential stereoisomers of these Chinese herbal medicines.

BackgroundCinobufacin injection, also known as huachansu, is a preparation form of Cinobufacini made from Cinobufacin extract liquid. Despite that Cinobufacin injection is shown to shrink liver and gastric tumors, improving patient survival and life quality, the effective components in Cinobufacin remain elusive. In this study, we aim to screen antitumor components from Cinobufacin injection to elucidate the most effective antitumor components for treatment of liver and gastric cancers.Materials and MethodsHigh performance liquid chromatography (HPLC) and LC-MS/MS analysis were used to separate and determine the components in Cinobufacin injection. Inhibition rates of various components in Cinobufacin injection on liver and gastric cancer cells were determined with MTT assay; Hepatocellular carcinoma and gastric cancer models were used to assess the antitumor effect of the compounds in vivo.ResultsThe major constituents in Cinobufacin injection include peptides, nucleic acids, tryptamines and bufotalins. MTT assay revealed that bufadienolides had the best antitumor activity, with peptides being the second most effective components. Bufadienolides showed significant inhibition rates on gastric and hepatocellular tumour growth in vivo.ConclusionBufadienolides are the most effective components in Cinobufacini injection for the treatment of liver and gastric cancers. This discovery can greatly facilitate further research in improving the therapeutic effects of Cinobufacin injection, meanwhile reducing its adverse reaction.